The LTC®4355 is a positive voltage ideal diode-OR controller that drives two external N-channel MOSFETs. Forming the diode-OR with N-channel MOSFETs instead of Schottky diodes reduces power consumption, heat dissipation and
PC board area. With the LTC4355, power sources can easily be ORed together to increase total system reliability. The LTC4355 can diode-OR two positive supplies or the return paths of two negative supplies, such as in a –48V system.

In the forward direction the LTC4355 controls the voltage drop across the MOSFET to ensure smooth current transfer from one path to the other without oscillation. If a power source fails or is shorted, fast turnoff minimizes
reverse current transients. Power fault detection indicates if the input supplies are not in regulation, the inline fuses are blown, or the voltages across the MOSFETs are greater than the fault threshold.

The TPS73118DBVT is a 1.8V fixed output low-dropout (LDO) Linear Regulator with reverse current protection uses a new topology, an NMOS pass element in a voltage-follower configuration. This topology is stable using output capacitors with low equivalent series resistance (ESR) and even allows operation without a capacitor. The device also provides high reverse blockage (low reverse current) and ground pin current that is nearly constant over all values of output current. The device uses an advanced BiCMOS process to yield high precision while delivering very low-dropout (LDO) voltages and low ground pin current. Current consumption, when not enabled, is less than 1µA and ideal for portable applications. The extremely low output noise is ideal for powering VCOs. These devices are protected by thermal shutdown and fold-back current limit.

• Stable with or without capacitors of all types
• Excellent load transient response-with or without optional output capacitor
• New NMOS topology provides low reverse leakage current
• 30µVrms Low noise (10kHz to 100kHz)
• 0.5% Initial accuracy
• 1% Overall accuracy over line, load and temperature
• <1µA Quiescent current (IQ) in shutdown mode
• Thermal shutdown and specified minimum and maximum current limit protection
• Green product and no Sb/Br

The LP38855S-1.2 is a 1.8V fixed output fast-response high-accuracy low-dropout (LDO) Linear Regulator with Enable. The device can maintain output voltage regulation with an extremely low input to output voltage drop. Fabricated on a CMOS process, the device operates from two input voltages, VBIAS provides power for the internal bias and control circuits, as well as drive for the gate of the N-MOS power transistor, while VIN supplies power to the load. The use of an external bias rail allows the part to operate from ultra-low VIN voltages. Unlike bipolar regulators, the CMOS architecture consumes extremely low quiescent current at any output load current. The use of an N-MOS power transistor results in wide bandwidth, yet minimum external capacitance is required to maintain loop stability. The fast transient response of this device makes it suitable for use in powering DSP, microcontroller core voltages and switch mode power supply post regulators.

• Stable with 10µF ceramic capacitors
• ±1.0% Precision output voltage across all line and load conditions (TJ = 25°C)
• Overtemperature and overcurrent protection